2001 Ski-Doo Factory Shop Manual Volume One, Page 175Get this manual
Section 04 ENGINE Subsection 10 (CARBURETOR AND FUEL PUMP)
PUMP VERIFICATION
Check fuel pump valves operation as follows: Connect clean plastic tubing to the inlet nipple and alternately apply pressure and vacuum with pump of leak test kitThe inlet valve should release with pressure and hold under vacuumRepeat the same procedure at the outlet nippleThis time the outlet valve should hold with pressure and release under vacuumNOTE: On model fitted with outlets, plug outlet with finger while checking outlet valveCheck impulse diaphragm and gasket on high-supply fuel pump with twin outlets as follows: Connect clean plastic tubing to the impulse nipple and plug vent hole on top coverEither apply pressure or vacuumThe diaphragmgasket must not leak